Audi unveils the E-Tron GT Concept
Audi shows off its electric future in the E-Tron GT concept
01:03 - Source: CNN
London CNN Business  — 

The next generation of electric cars could charge their batteries in the time it takes to fill up at a gas station.

A group of companies including Germany’s BMW (BMWYY), Porsche and Siemens (SIEGY) say they have developed technology that could help make super-fast charging a reality.

They unveiled on Thursday a 450 kW charging station that needs only three minutes to provide enough juice for a 100 kilometer (62 miles) drive. A full charge takes 15 minutes.

Ian Ellerington, head of technology transfer at the Faraday Institution, said the technology is significantly better than what’s currently available, even if there are major issues to resolve before it’s put into widespread use.

“450kW is substantially quicker than the Tesla superchargers (120kW), and would in principle be 10 times quicker than the rapid chargers that are currently widely available,” he said.

The slow charging problem

Long charging times are a major drawback of electric cars currently on the market. They slow down road trips, and they’re a major inconvenience for owners who can’t charge their cars at home.

Ellerington said the next generation of chargers could help solve the problem.

“At 350-450kW, electric charging will take a time comparable to refueling with gasoline, which will make long journeys in [electric vehicles] as practical as in cars using liquid fuels,” he said.

Power trouble

More development work is needed to make 450 kW chargers a practical option, however.

According to Ellerington, one major piece of the puzzle is building cars that can handle the increased power.

“I believe that there are no vehicles currently on the market that could accept this amount of power, and it will need the next generation of batteries to take advantage of the full capability,” he said.

For the 450 kW charging project, BMW and Porsche designed cars specifically for the tests.

Keith Pullen, a professor of energy systems at City, University of London, said that super-fast charging comes with other drawbacks.

“If you charge a battery very quickly, it’s less efficient [and] it actually damages the battery,” he said.

The technology could be useful in an emergency, but frequent use would cause a battery to wear out quickly.

Draining the grid

Engineers would need to solve another problem: super-fast chargers use a huge amount of power.

Pullen said that a service station with 20 charging stations would use about six megawatts of power — the same amount as a typical small town.

“This power has to come from somewhere and it has to come from the grid,” he said. “You wouldn’t be able to roll this out, there have to be major changes first.”